The purpose of the Clinical Data and Outcomes Core is to provide longitudinal clinical, laboratory, and specimen locating data efficiently, and safely to basic, clinical, health services research, and epidemiological investigators affiliated with the UCSD CFAR. The large volume of both basic and clinical research conducted within the CFAR assures that, if appropriate datasets and querying capability were available, many opportunities for translational research would arise. Specifically, the goals of this core are to: 1. Facilitate more uniform and comprehensive assessment of key variables across clinical HIV sites at UCSD to facilitate the conduct of basic, clinical, epidemiologic, health services, and translational research; 2. To develop a data warehouse to facilitate linking of data from various sources for the purpose of constructing new datasets to support CFAR administration as well as feasibility and definitive studies; and, 3. To collaborate in and initiate projects relating laboratory, clinical, and health system/social/economic findings. We anticipate that this core will be useful to: a) basic science investigators in need of clinical correlates of patients whose specimens are being analyze, or wishing to select specimens based on specific characteristic; b) clinical investigators needing to know distributions of clinical or laboratory parameters for potential study populations to estimate sample or effects sizes for proposal preparation; c) investigators needing outcome information (e.g. survival, quality of life measures, CD4 and viral load outcomes) on subsets of patients of interest and; (d) investigators wanting to conduct observation studies prospective or retrospectively by assembling cohorts with defined characteristics that are recorded in the primary health care or clinical databases maintained by CFAR affiliated investigators.